Considerations
When using dynamic writing with a reader resource as the schema source in FME Workbench, you may see a log message similar to this:
“Cannot find a matching schema named '<Feature type name>' in the known set of schemas: 'CSV'. Known schema sources are: 'CSV2_1'. Please verify writer feature type configuration.”
This happens when the schema name expected by the writer does not match the schema name generated by the reader.
Why This Happens
Some readers generate schema names automatically, and those names cannot be changed after the schema is created.
For example, the CSV reader can generate a schema name based on:
- The format name, such as CSV
- The dataset file name
Some raster readers can behave similarly.
If no reader feature type is visible on the canvas, the generated schema name may not be obvious in the workspace. In that case, the Translation Log is usually the best place to confirm which schema name was created.
In the example above, the reader generated the schema name 'CSV', but the writer was looking for a different one. Because the names do not match, dynamic writing cannot find the correct schema.
How to Resolve It
Use one of the following approaches to ensure the writer references the same schema name as the reader.
Option 1: Match the Schema Definition Name
If the reader generated the schema name CSV, update the writer to use that same value for the schema definition. In the parameters set:
- Schema Definition Name: CSV
This is the simplest fix when the schema name is already clear from the log message.
Option 2: Regenerate the Reader Feature Type Using the File Name
If you want the schema name to be easier to identify, regenerate the reader feature type to use the dataset file name.
Remove and re-add the reader. In the reader parameters, set:
- Feature Type Name(s): From File Name
Finish adding the reader and confirm the reader feature type appears on the canvas. Update the writer so that the schema definition matches the generated name.
This approach can make dynamic writing easier to configure because the schema name is more visible and predictable.
Additional Notes
Some readers do not make the generated schema name obvious unless the reader feature type is shown on the canvas.
When troubleshooting schema mismatches, check the Translation Log first. It will often show both:
- The schema name the writer expected
- The schema name the reader actually generated
That comparison usually makes the mismatch clear.
Additional Resources
Dynamic Workspaces documentation